IPAC2012 - List of Authors (Seiya, K.)

Paper	Title	Page
MOPPC018	Single/Few Bunch Space Charge Effects at 8 GeV in the Fermilab Main Injector	163
	D.J. Scott, D. Capista, I. Kourbanis, K. Seiya, M.-J. Yang Fermilab, Batavia, USA
	For Project X, it is planned to inject a beam of 3 10¹¹ particles per bunch into the Main Injector. Therefore, at 8 GeV, there will be increased space charge tune shifts and an increased incoherent tune spread. In preparation for these higher intensity bunches exploratory studies have commenced looking at the transmission of different intensity bunches at different tunes. An experiment is described with results for bunch intensities between 20 and 172 10⁹ particles. To achieve the highest intensity bunches coalescing at 8 GeV is required, resulting in a longer bunch length. Comparisons show that similar transmission curves are obtained when the intensity and bunch length have increased by factors of 3.2 and 3.4 respectively, indicating the incoherent tune shifts are similar, as expected from theory. The results of these experiments will be used in conjugation with simulations to further study high intensity bunches in the Main Injector.

THPPP021	6 Batch Injection and Slipped Beam Tune Measurements in Fermilab’s Main Injector	3776
	D.J. Scott, D. Capista, I. Kourbanis, K. Seiya, M.-J. Yang Fermilab, Batavia, USA
	During Nova operations it is planned to run the Fermilab Recycler in a 12 batch slip stacking mode. In preparation for this, measurements of the tune during a six batch injection and then as the beam is slipped by changing the RF frequency, but without a 7th injection, have been carried out in the Main Injector. The coherent tune shifts due to the changing beam intensity were measured and compared well with the theoretically expected tune shift. The tune shifts due to changing RF frequency, required for slip stacking, also compare well with the linear theory, although some nonlinear affects are apparent at large frequency changes. These results give us confidence that the expected tunes shifts during 12 batch slip stacking Recycler operations can be accommodated.

THPPP022	Coalescing at 8 GeV in the Fermilab Main Injector	3779
	D.J. Scott, D. Capista, I. Kourbanis, K. Seiya, M.-J. Yang Fermilab, Batavia, USA
	For Project X, it is planned to inject a beam of 3 10¹¹ particles per bunch into the Main Injector. To prepare for this by studying the effects of higher intensity bunches in the Main Injector it is necessary to perform coalescing at 8 GeV. The results of a series of experiments and simulations of 8 GeV coalescing are presented. To increase the coalescing efficiency adiabatic reduction of the 53 MHz RF is required, resulting in ~70% coalescing efficiency of 5 initial bunches. Data using wall current monitors has been taken to compare previous work and new simulations for 53 MHz RF reduction, bunch rotations and coalescing, good agreement between experiment and simulation was found. Possible schemes to increase the coalescing efficiency and generate even higher intensity bunches are discussed. These require improving the timing resolution of the low level RF and/or tuning the adiabatic voltage reduction of the 53 MHz.

THPPP023	Momentum Cogging at the Fermilab Booster	3782
	K. Seiya, C.C. Drennan, W. Pellico, A.K. Triplett, A.M. Waller Fermilab, Batavia, USA
	The Fermilab booster has an intensity upgrade plan called the Proton Improvement plan (PIP). The flux throughput goal is 2·10¹⁷ protons/hour which is almost double the current operation at 1.10¹⁷ protons/hour. The beam loss in the machine is going to be an issue. The booster accelerates beam from 400 MeV to 8GeV and extracts to The Main Injector (MI). Cogging is the process that synchronizes the extraction kicker gap to the MI by changing radial position of the beam during the cycle. The gap creation occurs at about 700MeV which is 6msec into the cycle. The variation of the revolution frequency from cycle to cycle is larger at lower energy and it is hard to control by changing the radial position because of aperture limitations. Momentum cogging is able to move the gap creation earlier by using dipole correctors and radial position feedback, and controlling the revolution frequency and radial position at the same time. The new cogging is going to save energy loss and aperture. The progress of the momentum cogging system development is going to be discussed in this paper.

THPPP024	Alignment and Aperture Scan at the Fermilab Booster	3785
	K. Seiya, J.R. Lackey, W.L. Marsh, W. Pellico, D.A. Still, A.K. Triplett, A.M. Waller Fermilab, Batavia, USA
	The Fermilab booster has an intensity upgrade plan called the Proton Improvement plan (PIP). The flux throughput goal is 2·10¹⁷ protons/hour, which is almost double the current operation at 1.10¹⁷ protons/hour. The beam loss in the machine is going to be the source of issues. The booster accelerates beam from 400 MeV to 8 GeV and extracts to the Main Injector. Several percent of the beam is lost within 3 msec after the injection. The aperture at injection energy was measured and compared with the survey data. The magnets are going to be realigned in March 2012 in order to increase the aperture. The beam studies, analysis of the scan and alignment data, and the result of the magnet moves will be discussed in this paper.

Paper

Title

Page

Single/Few Bunch Space Charge Effects at 8 GeV in the Fermilab Main Injector

163

D.J. Scott, D. Capista, I. Kourbanis, K. Seiya, M.-J. Yang
Fermilab, Batavia, USA

For Project X, it is planned to inject a beam of 3 10¹¹ particles per bunch into the Main Injector. Therefore, at 8 GeV, there will be increased space charge tune shifts and an increased incoherent tune spread. In preparation for these higher intensity bunches exploratory studies have commenced looking at the transmission of different intensity bunches at different tunes. An experiment is described with results for bunch intensities between 20 and 172 10⁹ particles. To achieve the highest intensity bunches coalescing at 8 GeV is required, resulting in a longer bunch length. Comparisons show that similar transmission curves are obtained when the intensity and bunch length have increased by factors of 3.2 and 3.4 respectively, indicating the incoherent tune shifts are similar, as expected from theory. The results of these experiments will be used in conjugation with simulations to further study high intensity bunches in the Main Injector.

THPPP021

6 Batch Injection and Slipped Beam Tune Measurements in Fermilab’s Main Injector

3776

D.J. Scott, D. Capista, I. Kourbanis, K. Seiya, M.-J. Yang
Fermilab, Batavia, USA

During Nova operations it is planned to run the Fermilab Recycler in a 12 batch slip stacking mode. In preparation for this, measurements of the tune during a six batch injection and then as the beam is slipped by changing the RF frequency, but without a 7th injection, have been carried out in the Main Injector. The coherent tune shifts due to the changing beam intensity were measured and compared well with the theoretically expected tune shift. The tune shifts due to changing RF frequency, required for slip stacking, also compare well with the linear theory, although some nonlinear affects are apparent at large frequency changes. These results give us confidence that the expected tunes shifts during 12 batch slip stacking Recycler operations can be accommodated.

THPPP022

Coalescing at 8 GeV in the Fermilab Main Injector

3779

D.J. Scott, D. Capista, I. Kourbanis, K. Seiya, M.-J. Yang
Fermilab, Batavia, USA

For Project X, it is planned to inject a beam of 3 10¹¹ particles per bunch into the Main Injector. To prepare for this by studying the effects of higher intensity bunches in the Main Injector it is necessary to perform coalescing at 8 GeV. The results of a series of experiments and simulations of 8 GeV coalescing are presented. To increase the coalescing efficiency adiabatic reduction of the 53 MHz RF is required, resulting in ~70% coalescing efficiency of 5 initial bunches. Data using wall current monitors has been taken to compare previous work and new simulations for 53 MHz RF reduction, bunch rotations and coalescing, good agreement between experiment and simulation was found. Possible schemes to increase the coalescing efficiency and generate even higher intensity bunches are discussed. These require improving the timing resolution of the low level RF and/or tuning the adiabatic voltage reduction of the 53 MHz.

THPPP023

Momentum Cogging at the Fermilab Booster

3782

K. Seiya, C.C. Drennan, W. Pellico, A.K. Triplett, A.M. Waller
Fermilab, Batavia, USA

The Fermilab booster has an intensity upgrade plan called the Proton Improvement plan (PIP). The flux throughput goal is 2·10¹⁷ protons/hour which is almost double the current operation at 1.10¹⁷ protons/hour. The beam loss in the machine is going to be an issue. The booster accelerates beam from 400 MeV to 8GeV and extracts to The Main Injector (MI). Cogging is the process that synchronizes the extraction kicker gap to the MI by changing radial position of the beam during the cycle. The gap creation occurs at about 700MeV which is 6msec into the cycle. The variation of the revolution frequency from cycle to cycle is larger at lower energy and it is hard to control by changing the radial position because of aperture limitations. Momentum cogging is able to move the gap creation earlier by using dipole correctors and radial position feedback, and controlling the revolution frequency and radial position at the same time. The new cogging is going to save energy loss and aperture. The progress of the momentum cogging system development is going to be discussed in this paper.

THPPP024

Alignment and Aperture Scan at the Fermilab Booster

3785

K. Seiya, J.R. Lackey, W.L. Marsh, W. Pellico, D.A. Still, A.K. Triplett, A.M. Waller
Fermilab, Batavia, USA

The Fermilab booster has an intensity upgrade plan called the Proton Improvement plan (PIP). The flux throughput goal is 2·10¹⁷ protons/hour, which is almost double the current operation at 1.10¹⁷ protons/hour. The beam loss in the machine is going to be the source of issues. The booster accelerates beam from 400 MeV to 8 GeV and extracts to the Main Injector. Several percent of the beam is lost within 3 msec after the injection. The aperture at injection energy was measured and compared with the survey data. The magnets are going to be realigned in March 2012 in order to increase the aperture. The beam studies, analysis of the scan and alignment data, and the result of the magnet moves will be discussed in this paper.